Field evaluation of some selected plant materials for the control of major insect pests of cowpea (Vigna unguiculata(L.) Walp.) in the Northern Guinea Savannah of Nigeria

Abstract

Field experiments were carried out at the Teaching and Research Farm of the Abubakar Tafawa Balewa University, Bauchi during the rainy season of 2005. The study was carried out with sole objective of evaluating the efficacy of six selected plant materials (sweetsop, red pepper, garlic, neem, mahogany and gmalina) against the major insect pests of cowpea variety, Dan Sokoto. The experiment was laid down in randomised complete block design with seven treatments. Each treatment was replicated three times. The results of the study showed that all the plant materials used were significantly (p < 0.05) better than control where no plant material was used in controlling the population of B. tabaci, E. dolichi, M. sjostedti and C. tomentosicollis at 1, 2 and 3 days after application of the treatments. Similarly the effects of these plant materials on the number of seeds/pod showed a significant (p < 0.05) difference between plots treated with plant materials and control. On the grain yield of the crop, all the plant materials showed significant effect except mahogany and the control which were statistically similar. Furthermore, the order of level of control indicated that sweet sop has (70.7%), garlic (69.3%), neem (61.0%), red pepper (54.0%), ash (30.9%), and mahogany (3.5%). The result of the present finding therefore recommends the use of sweet sop, garlic and neem as they were found to be the most promising in the control of major cowpea insect pests.     

Lymphatic Endothelial Differentiation in Pulmonary Lymphangioleiomyomatosis Cells

Pulmonary lymphangioleiomyomatosis (LAM) is a rare, low-grade neoplasm affecting almost exclusively women of childbearing age. LAM belongs to the family of perivascular epithelioid cell tumors, characterized by spindle and epithelioid cells with smooth muscle and melanocytic differentiation. LAM cells infiltrate the lungs, producing multiple, bilateral lesions rich in lymphatic channels and forming cysts, leading to respiratory insufficiency. Here we used antibodies against four lymphatic endothelial markers—podoplanin (detected by D2-40), prospero homeobox 1 (PROX1), vascular endothelial growth factor receptor 3 (VEGFR-3), and lymphatic vessel endothelial hyaluronan receptor 1 (LYVE1)—to determine whether LAM cells show lymphatic differentiation. Twelve of 12 diagnostic biopsy specimens (early-stage LAM) and 19 of 19 explants (late-stage LAM) showed immunopositivity for D2-40 in most neoplastic cells. PROX1, VEGFR-3, and LYVE1 immunoreactivity varied from scarce in the early stage to abundant in the late stage. Lymphatic endothelial, smooth muscle, and melanocytic markers were partially co-localized. These findings indicate that lymphatic endothelial differentiation is a feature of LAM and provide evidence of a previously unidentified third lineage of differentiation in this neoplasm. This study has implications for the histological diagnosis of LAM, the origin of the neoplastic cells, and potential future treatment with drugs targeting lymphangiogenesis.     

MicroRNA-21与平滑肌蛋白22α在哈萨克族食管癌组织中的表达及其临床病理学意义

目的探讨microRNA21与SM22a基因在哈萨克族食管癌发生发展中的作用及临床意义。方法免疫组织化学法检测162例石蜡包埋食管鳞状细胞癌组织及RT-PCR方法检测47例哈萨克族食管癌标本中microRNA21、SM22a表达水平,分析这些基因与临床病理特征的关系。结果SM22a在162例食管鳞癌组织中的阳性表达率(87.0%)显著高于食管正常黏膜组织(36.0%);在47例哈萨克族食管癌组织中,SM22a表达水平较远端无癌组织增高。与远端无癌组织相比,microRNA21在哈萨克族食管癌组织中表达水平增高。MicroRNA21高表达与分化程度、淋巴结转移、临床分期相关,SM22a高表达与临床分期相关、淋巴结转移相关;microRNA21与SM22a的表达呈正相关。结论MicroRNA21、SM22a协同高表达共同参与哈萨克族食管癌的侵袭发展过程。     

Does glutathione S-transferase Pi (GST-Pi) a marker protein for cancer?

Glutathione S-transferases (GSTs, EC 2.5.1.18) are multifunctional and multigene products. They are versatile enzymes and participate in the nucleophilic attack of the sulphur atom of glutathione on the electrophilic centers of various endogenous and xenobiotic compounds. Out of the five, , and , major classes of GSTs, GST- has significance in the diagnosis of cancers as it is expressed abundantly in tumor cells. This protein is a single gene product, coded by seven exons, that is having 24 kDa mass and pI value of 7.0. Four upstream elements such as two enhancers, and one of each of AP-1 site and GC box regulate gene. During chemical carcinogenesis because of jun/fos oncogenes (AP-1) regulatory elements, specifically GST- is expressed in liver. Therefore this gene product could be used as marker protein for the detection of chemical toxicity and carcinogenesis.     

Eukaryote-specific motif of ribosomal protein S15 neighbors A site codon during elongation and termination of translation

The eukaryotic ribosomal protein S15 is a key component of the decoding site in contrast to its prokaryotic counterpart, S19p, which is located away from the mRNA binding track on the ribosome. Here, we determined the oligopeptide of S15 neighboring the A site mRNA codon on the human 80S ribosome with the use of mRNA analogues bearing perfluorophenyl azide-modified nucleotides in the sense or stop codon targeted to the 80S ribosomal A site. The protein was cross-linked to mRNA analogues in specific ribosomal complexes that were obtained in the presence of eRF1 in the experiments with mRNAs bearing stop codon. Digestion of modified S15 with various specific proteolytic agents followed by identification of the resulting modified oligopeptides showed that cross-link was in C-terminal fragment in positions 131–145, most probably, in decapeptide 131-PGIGATHSSR-140. The position of cross-linking site on the S15 protein did not depend on the nature of the A site-bound codon (sense or stop codon) and on the presence of polypeptide chain release factor eRF1 in the ribosomal complexes with mRNA analogues bearing a stop codon. The results indicate an involvement of the mentioned decapeptide in the formation of the ribosomal decoding site during elongation and termination of translation. Alignment of amino acid sequences of eukaryotic S15 and its prokaryotic counterpart, S19p from eubacteria and archaea, revealed that decapeptide PGIGATHSSR in positions 131–140 is strongly conserved in eukaryotes and has minor variations in archaea but has no homology with any sequence in C-terminal part of eubacterial S19p, which suggests involvement of the decapeptide in the translation process in a eukaryote-specific manner.     

Doubly Spin-Labeled RNA as an EPR Reporter for Studying Multicomponent Supramolecular Assemblies

mRNAs are involved in complicated supramolecular complexes with human 40S and 80S ribosomes responsible for the protein synthesis. In this work, a derivative of nonaribonucleotide pUUCGUAAAA with nitroxide spin labels attached to the 5′-phosphate and to the C8 atom of the adenosine in sixth position (mRNA analog) was used for studying such complexes using double electron-electron resonance/pulsed electron-electron double resonance spectroscopy. The complexes were assembled with participation of tRNA^Phe, which targeted triplet UUC of the derivative to the ribosomal peptidyl site and predetermined location of the adjacent GUA triplet coding for Val at the aminoacyl (A) site. The interspin distances were measured between the two labels of mRNA analog attached to the first nucleotide of the peptidyl site bound codon and to the third nucleotide of the A site bound codon, in the absence/presence of second tRNA bound at the A site. The values of the obtained interspin distances agree with those calculated for available near-atomic structures of similar complexes of 40S and 80S ribosomes, showing that neither 60S subunit nor tRNA at the A site have a noticeable effect on arrangement of mRNA at the codon-anticodon interaction area. In addition, the shapes of distance distributions in four studied ribosomal complexes allowed conclusions on conformational flexibility of mRNA in these complexes. Overall, the results of this study are the first, to our knowledge, demonstration of double electron-electron resonance/pulsed electron-electron double resonance application for measurements of intramolecular distances in multicomponent supramolecular complexes involving intricate cellular machineries and for evaluating dynamic properties of ligands bound to these machineries.     

EphA2 Mutation in Lung Squamous Cell Carcinoma Promotes Increased Cell Survival,Cell Invasion,Focal Adhesions,and Mammalian Target of Rapamycin Activation

Non-small cell lung cancer (NSCLC) has a poor prognosis and improved therapies are needed. Expression of EphA2 is increased in NSCLC metastases. In this study, we investigated EphA2 mutations in NSCLC and examined molecular pathways involved in NSCLC. Tumor and cell line DNA was sequenced. One EphA2 mutation was modeled by expression in BEAS2B cells, and functional and biochemical studies were conducted. A G391R mutation was detected in H2170 and 2/28 squamous cell carcinoma patient samples. EphA2 G391R caused constitutive activation of EphA2 with increased phosphorylation of Src, cortactin, and p130^Cas. Wild-type (WT) and G391R cells had 20 and 40% increased invasiveness; this was attenuated with knockdown of Src, cortactin, or p130^Cas. WT and G391R cells demonstrated a 70% increase in focal adhesion area. Mammalian target of rapamycin (mTOR) phosphorylation was increased in G391R cells with increased survival (55%) compared with WT (30%) and had increased sensitivity to rapamycin. A recurrent EphA2 mutation is present in lung squamous cell carcinoma and increases tumor invasion and survival through activation of focal adhesions and actin cytoskeletal regulatory proteins as well as mTOR. Further study of EphA2 as a therapeutic target is warranted.     

The epidemiology of HIV and AIDS in the world

The worldwide epidemic of HIV continues to expand in many regions of the world, particularly in southern Africa, South and Southeast Asia, East Asia and Eastern Europe and Central Asia. Estimates are that at the end of 2005 there were 38.6 million persons living with HIV infection and that 4.1 million new infections and 2.8 million deaths from HIV occurred during the year. Regionally different patterns predominate from generalized heterosexual epidemics in sub-Saharan Africa and parts of the Caribbean to mixes of epidemics in which transmission among injection drug users, their sexual partners, commercial sex workers and their partners intersect. Multilateral and bilateral antiretroviral access campaigns, such as the World Health Organization's 3 x 5 initiative, have resulted in broader access to live-saving therapy for infected persons in low- and middle-income countries, but several million infected people who are clinically eligible for antiretroviral therapy remain untreated. The public health challenge worldwide is to keep the uninfected and to treat and care for those who have already been infected.     

甘肃、新疆、内蒙苹果蠹蛾成虫消长规律

苹果蠹蛾Cydia pomonella(L.)是我国重要的果树害虫和检疫对象。2005年至2010年,本研究在甘肃、新疆及内蒙古的不同区县选取了16个果园,使用性信息素诱捕器对其中的苹果蠹蛾成虫发生规律进行长期监测。结果表明,苹果蠹蛾在西北地区每年发生2.5个世代;在正常气候条件下,3个成虫发生高峰分别出现在5月上旬、7月中下旬和8月中下旬,但不同地区及同一地区不同果园之间存在较大差异;化学防治、迷向防治等防治措施对苹果蠹蛾成虫捕获量的影响较大,因此生活史研究为主的监测并不适合在上述果园中开展。综合上述研究结果,未对苹果蠹蛾的季节动态进行准确的预测,需要对苹果蠹蛾除成虫外的其他虫态的季节性变化进行详细研究,并建议选择3个以上的果园进行监测,综合各个果园的监测结果并得出结论。     

Evaluation of physiological importance of metallothionein protein expressed by Tetrahymena cadmium metallothionein 1 (TMCd1) gene in Escherichia coli

TMCd1 is a cadmium inducible metallothionein (MT) gene. In the present study the TMCd1 gene of a ciliate protozoan has been expressed in E. coli and the function of the expressed TMCd1 protein as a metal-binding protein has been evaluated. The growth of E. coli cells expressing the GST fused TMCd1 proteins in the presence of cadmium metal clearly demonstrated the role of TMCd1 as a metal-binding protein. The metal accumulation experiments showed that the bacterial cells expressing the functional TMCd1 protein accumulated 19-fold more cadmium in contrast to control cells that lacked the TMCd1 protein expression. The results clearly demonstrate a physiological role of full length TMCd1 protein of a ciliate, expressed in E. coli, in cadmium metal sequestration and detoxification.